Feed control mechanism



May 8, 1934- G. M. NELL. 1,957,976

FEED CONTROL MECHANISM Filed April 2, 1931 A TTORNE Y.

Patented May S, 1934 UNITI) STATES FEED CONTROL MECHANISM Application April 2, 1931, Serial No. 527,174

Claims.

This invention relates to control mechanism for uid pressure motors. relates to machines adapted and intended for manual direction and control such as stoping 5- drills which include both a uid pressure percussive motor and a fluid pressure feeding motor.

One object of the invention is to devise an improved form of holding or control handle for stoper drills. Another object is to effect positive control of one of the motors of a stoping drill without interfering with the utilization of the handle for a lubricant reservoir. Still another object is to protect the control parts from accidental damage and to avoid interference with the I; same even though the handle should become bent. Other objects include simplicity-accessibility of parts and cheapness in cost of manufacture. Still other advantages will be apparent from the detailed description which follows.

The invention provides a compact and conveniently operated control arrangement in which the parts are so arranged in the conventional holding or rotating handle asto permit the use of the oil reservoir common in such handles. By 2r;` preference the control parts are disposed axially and centrally of the handle portion extending transversely of the machine. An operating rod for positively actuating a control valve eX- tends through the handle and is operated by a push button adjacent the grip portion of the handle. A tube extending entirely through the handle provides a passage in which the operating rod is slidably mounted and the tube is welded or otherwise secured at its ends in a fluid tight manner so as to provide within the hollow handle a lubricant chamber encircling the operating rod. By preference the rod is flexible to the end that bending of the handle will not affect its operation.

40 In order to illustrate the invention one concrete embodiment thereof is shown -in the accompanying drawing, in which:

Fig. 1 is a fragmentary Vertical sectional View in two offset vertical planes of the central por- .15v tion of a iiuid pressure percussive stoping drill; Fig. 2 is a detail sectional view of the control parts shown in Fig. 1 indicating the valve in its position to relieve pressure in the feed leg; and

Fig. 3 is a fragmentary elevational View 0f the outer end of the control handle.

Fig. 4 is a fragmentary sectional view similar to Fig. 2 but on a larger scale.

The embodiment of the invention chosen for the purpose of illustration comprises a fluid pressure percussive stoping machine but only such More particularly it (c1. iai-9)' parts thereof are shown as is necessary for an understanding of the invention.` The machine comprises a iiuid pressure percussive motor indicated generally at A and a fluid pressure operated feed motor indicated generally at B for advancing motor A to the work, the two mechanisms being connected by an interposed head 4. Motor A may comprise a cylinder 5 in which reciprocates a hammer piston 6 having a recess in the rear endthereof inV which is mounted a rifle nut 7 cooperating with a riiie bar 8. The parts of the feed leg B comprise a cylinder 9 slidably receiving feed piston 1) which carries packings 11 to make a fluid tight fit with the cylinder Wall. Since both the percussive motor A and the feed leg B may be Wholly conventional and of any suitable or desired type, and since the functioning of the control apparatus comprising the present invention is not dependent upon any specific type of rock drilling mechanism to which it may be attached, further disclosure anddescription thereof is omitted. Y

Member or head 4 between motors A and B has a transverse bore 4a therethrough which is inwardly tapered from the left side and has a large counterbore and a short inward taper from the right side as clearly indicated in Figs. 1 and 2. A plug 12 conforming to the taper of the left side is inserted therein and a manual control and rotating handle 13 is inserted from the opposite side. The inner end of handle 13 has a taper to conform to the inward taper on the right side of bore 4a and its extreme end is eXteriorly threaded to cooperate with internal threads on plug 12 so that handle 13 screws into plug 12 to secure the control assembly in place. A sleeve nut 14 screws into the counterbore on the right side of head 4 to lock handle 13 against rotation.

Slidably mounted in a bore within plug 12 is a sleeve valve 15 for controlling the supply and release of pressure fluid to and from one of the motors, in this instance feed leg B. Valve 15 is yieldingly maintained in abutting relation to the inner end of handle 13 by a coil spring 16 which engages on the one hand the wall of plug 12 and on the otherl hand a plug 17 extending within the bore of valve 15 and secured therein by a pin or rivet 18. An operating member in the form of a rod 1g Yis secured in any suitable manner to plug 17 as by a welded or brazed connection and eX- tends-through' hollow handle 13 and terminates in a push button 20 projecting beyond the grip portion 13a of the handle whereby valve 15 may be positively moved against the resistance of spring 16 to the pressure releasing position shown gages the opposite end of the tube.

in Fig. 2. The connection between rod 19 and button 20 may be by welding or brazing. By preference rod 19 is exible so that in the event that handle 13 becomes bent in service, the feed leg B may still be under control of the operator. The rod may be of well known commercial ilexible shafting consisting of one or more closely wound steel wire springs. It can be of any desired degree of flexibility for bending and of any desired degree of stiffness for longitudinal compression or tension.

Suitable means are provided for utilizing the hollow interior of handle 13 and grip portion 13a as a container for lubricant without interfering with its use as a protectingy enclosure for operating rod 19. To this end a tube 21 extends through the laterally projecting portion 13 of the handle,

the ends of the tube being secured to the handle in a fluid tight manner as by welding or brazing at 21a and 2lb, thus producing a passage through which operating rod 19' may extend. Plug I7 may have a sliding nt with the inner end of tube 21 while the stem of push button 20 slidabl'y en- One or more bushings 22 may be used within tube 21 to guide rod' 19 at other points. To protect push button 20 against accidental damage or operation, handle 13' has an arcuate or circular ange 13b pro- Y jecting therefrom over button 20, the extent of the flange and its location being clearly shown in Figs. 2: and 3.

The operation of the apparatus is as follows: With the parts in the usual or normal positions shown in Fig. 1, motive fluid released by a throttle valve (not shown) passes through a port 23 to an annular groove 24 in the exterior of plug 12, through a port 25 to an internal annular groove 26 in the plug, along annular groove 15a in valve 15 to a spaced internal groove 27' in the plug whence it has access to passage 28' leading to the interior of feed leg cylinder 9V for extending feed leg piston 10. The bore of the valve 15 communicates at all times with atmosphere by reason of registering ports 29 through plug 17'and'va1ve 15 opening into annular groove 15bv on the exterior ofV the valve in spaced relation to the first named groove 15a. Groove 15b registers'with an internalv groove 30 in plug 12 which connects with a passage 31 leading to atmosphere. When the operator wishes toweaken the feed ofthe stoper on account of a stuck steel or to collapse the stoper to withdraw it from the work, he presses upon push button 20 which operates through flexibleV rod 19 positively toV move valve 15 in- 'wardly against the pressure of spring 16 tothe position shown in Fig. 2-. Groove 15a of the valve, while still in communication with the motive fluid supply passage-23, is cut off from communication with passage 28 leading to the feed leg by the intervening ridge or ange 15c'0n the valve. At the same time the other valve groove 15bestablishes communication between internal grooves 27 and 30 of plug 12 so that the pressure uid in the feed leg cylinder 9 vents to atmosphere through atmospheric exhaust 31. The speed of the collapsing movement ofthe feed leg maybe regulated by the extent to which Valve 151 is moved tothe left by pressure on push button 20. To retard the collapsing of the feed leg, motive fluid in4 limited amount may be fedthereto through a suitably arranged restricted port (not shown) in valve 15 in accordance with known practice.

The-oil reservoir provided within handle 13 and its grip portion 13a. one wall of which reservoir is provided by tube 21, may be filled with lubricant through a suitably arranged opening closed by a plug 32 and the lubricant may be directed as desired through a port 33 and suitable registering passages in member 4 to any part of percussivc motor A or feed motor B and may be gradually forced from the reservoir by pulsations of air in the usual manner.

From the above it will be apparent that the present invention provides relatively remote positive controlling mechanism for a fluid pressure motor, such as the feed motor of a stoping drill, that this is accomplished with a minimum addition of weight to the machine, that the parts of the controlling mechanism usually subject to damage are well protected, that the controlling member is arranged to extend through the holding and rotating handle without requiring the omission of the usual lubricant reservoir, that the operating member is flexible so that even if the holding handle should become bent in service control of the feed motor will not be lost, and that the flexible operating member is positively secured to the control valve and extends within the guide tube to center the valve and guide its movement relative to the holding handle.

While the invention has been herein disclosed in what is now considered to be a preferred form, it is to be understood. that the invention is not limited to the specific details thereof but covers all changes, modifications, and adaptationswithin the scope of the appended` claims.

I claim as my invention:

1. A stoping drill having a percussive motor and fluid pressure feed motor for advancing the percussive motor to the work, a holding and rotating handle projecting laterally from said-drill and having a hollow interior forming a lubricant chamber, a tube extending through said handle and said chamber and secured in a fluidtight manner at its ends to provide an open` passage sealed from the lubricant chamber, and control means for one of said motorsincluding amanualily operable member movably mounted' in said passage.

2. A stopingdrill having a percussive motor and fluidpressure feed` motor for advancing the percussive motor to thework, a holdingiandrotating handle projecting laterally from said drilli and having a hollowl interior forming a lubricant chamber, a tube extending through said handle and said chamber andV secured in a fluid tight manner at the ends` of the lubricant chamber to provide an open passage sealed from the chamber, and control means-for one of said motors includingV a flexible member slidably mounted in said tube and arranged for manual operation.

3. In a stoping drill having a percussive motor and a fluid actuated feed leg, a valve for controlling said feed leg andk normally passing pressure fluid thereto, andi means providing in coaxial re'- lation and in line with the valve an operating member for-said valve andY a chamberv for lubricant, said operating memberY being sealedl from said lubricant chamber, the'walls-.of the lubricant chamber comprising parts rigidly secured" toeach other to prevent leakage'oflubricant to the valve.

4. A stoping drill having a percuss-ive motor and iiuid pressure feed motor for advancing the percussive motor'to the work, a holdingandrotating handle projecting laterally from said drill and having a hollow interior forming al lubricant chamber, a tube extendingy through said handle and said chamber and secured in a fluid tight manner at its ends to provide an open passage,

having a hollow interior forming a lubricant chamber, a tube extending through said handle and said chamber and secured in a uid tight manner at its ends to provide an open passage sealed from said lubricant chamber, and control means for one of said motors comprising a spring pressed valve in line with said handle, and a control member for said valve comprising a flexible rod within said passage and guide means for said rod slidably engaging the interior of said tube. GUSTAVE M. NELL. 

